1. Field of the Invention
The invention relates to an electronic device. Particularly, the invention relates to an electronic device including a rack.
2. Description of Related Art
A server is a computer placed in the core of a network system to service all other connected computers. A server computer provides network users their needed storage and printing services. It also enables all network clients to share the resources within the network environment. The basic structure of a server computer is quite similar to a Personal Computer which consists of one or more CPUs, Memory, Input/Output devices and other components. The components are connected to an internal Bus which connects to the CPU(s) and Memory through a North-Bridge controller chip and connects to Input/Output devices through a South-Bridge controller chip. The server chassis has evolved through three generations: the tower chassis, the rack mounted chassis (which provides good centralization), and the blade server (which provides high density computing capability).
Rack mounted servers, for example, have standardized outside dimensions which fit standard sized racks so that their cabinets can be standardized also. That is, rack mounted servers are an optimized version of tower servers. The purpose of its design is to reduce to the minimum the amount of space taken up by the servers. Most professional network equipments such as switches, routers and hardware firewalls have adopted rack mounted structure. They are flat like desk drawers. A server rack has a standard width of 19 inches. Height is measured in the unit of U where 1 U is 1.75 inches or 44.45 mm. Heights such as 1 U, 2 U, 4 U, 5 U, 7 U are commonly used with rack mounted servers.
The size of a typical cabinet also conforms to industry standards, usually from between 22 U and 42 U. Inside the cabinet, at each U heights, there are removable sliding support structure. Users may make adjustments according to the height of his network equipments such as servers, routers and disk array drives. When the equipment is installed into rack and cabinet, all of their input/output cables are brought out from the rear of cabinet (rack mounted servers have their input/output interfaces in the rear also). All cables are then placed within the cable conduit of the cabinet. Labels are attached to the cables for easier maintenance and management.
Generally speaking, all working units inside a rack mounted server must connect to outside devices and power supplies through network cables and power cables. With the increasing density of computing and storage units inside the cabinet, the number of network cables and power cables becomes so large as to make it difficult to manage and to connect or remove cables. A large number of cables piled up in the rear of cabinets tend to block air flow which makes heat dissipation a problem.